KR20230091390A - Method for manufacturing biogel, biogel manufactured thereby and absorbent article comprising the same - Google Patents

Abstract

The present invention is a method for producing a biogel that can increase economic feasibility and safety by reducing the drying time of the gel without using a separate organic solvent in the post-treatment process by using brine during the reaction or post-treatment process, thereby It relates to a prepared bio-gel and an absorbent article comprising the same.

Description

Method for manufacturing biogel, biogel produced thereby, and absorbent article containing the same

The present invention relates to a method for producing a biogel, a biogel prepared thereby, and an absorbent article including the same.

Super absorbent polymer (SAP) is a hydrophilic polymer that can absorb 30 to 50 times more water-soluble liquid than its own weight. It is a functional material with It is used for various purposes such as agricultural soil moisture regulators as well as disposable sanitary products such as infant/adult diapers and women's sanitary napkins. As the consumption of disposable sanitary products increases year by year, the amount of waste generated is also rapidly increasing. However, since SAP, a petroleum-based polymer, is a non-degradable material and causes serious environmental pollution during the process of incineration and landfill, it is necessary to develop a biodegradable absorbent material that can replace it.

Nanocellulose, a natural biomass resource, is an eco-friendly material that is abundant in nature, and can be used as a superabsorbent polymer such as SAP due to its large specific surface area and rich hydroxyl content. However, in the case of cellulose that has not been chemically treated such as a crosslinking reaction, it does not have a structure that retains moisture when absorbing moisture and flows in a highly viscous aqueous solution, so it cannot be applied to absorbent articles such as disposable sanitary products such as diapers and sanitary napkins. .

As an example of a method for preparing a cellulose-based superabsorbent polymer having a water-holding structure in order to compensate for this problem, a method of manufacturing by adding a cross-linking agent to modified cellulose in which a hydroxyl group of cellulose is substituted with a carboxy group is there is. However, when the conventional cellulose-based hydrogel is washed with water in the post-treatment process for washing residual chemicals and unreacted samples immediately after gel formation, the gel absorbs water, making it difficult to dehydrate and dry for a long time. It takes time, and washing with organic solvents such as ethanol and acetone in order to shorten the drying time requires a large cost and there is a risk of fire and explosion.

Therefore, compared to conventional SAP materials derived from fossil fuels, there is a need for a technology capable of producing an eco-friendly biogel that is biodegradable and has excellent physical properties such as water absorption and water retention, especially appropriate post-processing technology.

The present invention is a method for producing a bio-gel capable of improving economic efficiency and safety by reducing the drying time of the gel without using a separate organic solvent in the post-treatment process by using brine during the reaction or in the post-treatment process, and thereby To provide a prepared biogel.

In addition, the present invention is to provide a bio-gel having excellent biodegradability, being eco-friendly, and having excellent physical properties such as water absorption and water retention, and an absorbent article including the same.

However, the problem to be solved by the present invention is not limited to the above-mentioned problem, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

An exemplary embodiment of the present invention comprises the steps of preparing a cellulose suspension containing a cellulose raw material including at least one of a cellulose derivative and cellulose fibers; preparing a cellulose gel by adding an acrylic monomer, a polymerization initiator and a crosslinking agent to the cellulose suspension; immersing the cellulose gel in water or saline; washing the immersed cellulose gel; and preparing a cellulose gel mixture by mixing and homogenizing the washed cellulose gel and a salt.

In addition, one embodiment of the present invention provides a bio-gel prepared by the above manufacturing method and an absorbent article including the same.

In the manufacturing method according to an exemplary embodiment of the present invention, by using brine during the reaction or in the post-treatment process, the drying time of the gel can be shortened without using a separate organic solvent in the post-treatment process to more easily prepare the biogel. can

In addition, the biogel manufacturing method according to an exemplary embodiment of the present invention is biodegradable and thus environmentally friendly, and can efficiently manufacture a superabsorbent biogel having excellent physical properties such as water absorption and water retention.

In addition, the biogel and the absorbent article including the biogel according to an exemplary embodiment of the present invention may be biodegradable and thus eco-friendly, and may have excellent physical properties such as water absorption rate and water retention capacity.

Effects of the present invention are not limited to the above-mentioned effects, and effects not mentioned will be clearly understood by those skilled in the art from the present specification and accompanying drawings.

1 shows a photograph after drying for 24 hours of the biogel prepared in Examples 1-1 to 1-6.

Throughout the present specification, when a certain component is said to "include", it means that it may further include other components without excluding other components unless otherwise stated.

Throughout the present specification, when a member is said to be located “on” another member, this includes not only a case where a member is in contact with another member, but also a case where another member exists between the two members.

Hereinafter, the present invention will be described in more detail.

An exemplary embodiment of the present invention comprises the steps of preparing a cellulose suspension containing a cellulose raw material including at least one of a cellulose derivative and cellulose fibers; preparing a cellulose gel by adding an acrylic monomer, a polymerization initiator and a crosslinking agent to the cellulose suspension; immersing the cellulose gel in water or saline; washing the immersed cellulose gel; mixing and grinding the washed cellulose gel and salt; and preparing a cellulose gel mixture by mixing the pulverized cellulose gel with polar group-containing cellulose.

In the manufacturing method according to an exemplary embodiment of the present invention, by using brine during the reaction or in the post-treatment process, the drying time of the gel can be shortened without using a separate organic solvent in the post-treatment process to more easily prepare the biogel. can In addition, the biogel manufacturing method according to an exemplary embodiment of the present invention is biodegradable and thus environmentally friendly, and can efficiently manufacture a superabsorbent biogel having excellent physical properties such as water absorption and water retention.

According to an exemplary embodiment of the present invention, the cellulose suspension may include the cellulose raw material, and the cellulose raw material may include at least one of a cellulose derivative and a cellulose fiber.

According to an exemplary embodiment of the present invention, the method for producing the biogel includes preparing pulp using a biomass raw material; and preparing the cellulose fibers including at least one of cellulose microfibers and cellulose nanofibrils from the pulp. Through this, it is possible to manufacture the cellulose fibers included in the cellulose raw material.

According to an exemplary embodiment of the present invention, the biomass raw material may include at least one of a woody biomass raw material and a non-woody biomass raw material. Specifically, the woody biomass raw material may include at least one of coniferous wood chips and hardwood wood chips, but the type of the woody biomass raw material is not limited. In addition, the non-woody biomass raw material may include at least one of bamboo, kenaf, hemp, rice, bagasse, seaweed, corn cob, corn core, rice straw, rice hull, wheat straw, and sugarcane cob However, the type of the non-woody biomass raw material is not limited. By using the above-mentioned type of biomass raw material, it is possible to manufacture the bio-gel, which has high biodegradability and is an environmentally friendly material.

According to an exemplary embodiment of the present invention, preparing the pulp may include reacting the biomass raw material with a mixed solvent of a glycol ether-based solvent and an acid. That is, organic solvent pulp can be produced from the biomass raw material. Specifically, pulp may be formed by reacting a biomass raw material with a mixed solvent of a glycol ether solvent and an acid. When pulp is formed by reacting a biomass raw material with a mixed solvent of a glycol ether-based solvent and an acid, physical properties such as water absorption and water retention of the prepared biogel can be effectively improved.

According to an exemplary embodiment of the present invention, the mixed solvent may be a mixture of a glycol ether-based solvent and an acid. The glycol ether-based solvent is ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, propylene glycol methyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and dipropylene glycol methyl ether. However, the type of the glycol ether-based solvent is not limited. In addition, hydrochloric acid, sulfuric acid, nitric acid, etc. may be used as the acid, but the type of acid is not limited.

According to an exemplary embodiment of the present invention, the volume ratio of the glycol ether-based solvent and the acid in the mixed solvent may be 95:5 to 99:1. Specifically, the volume ratio of the glycol ether-based solvent and the acid included in the mixed solvent may be 96:4 to 98.5:1.5, 96.5:3.5 to 98:2, or 97:3 to 97.5:2.5. When the volume ratio of the glycol ether-based solvent and the acid contained in the mixed solvent is within the above range, pulp can be effectively produced from the biomass raw material.

According to an exemplary embodiment of the present invention, in the step of forming the pulp, the mixed solvent may be reacted at a mixing ratio of 1L to 3L with respect to 1 Kg of the biomass raw material. Specifically, the mixing ratio of the mixed solvent with respect to 1 Kg of the biomass raw material may be 1.5L to 2.5L, or 2L. By adjusting the mixing ratio of the biomass raw material and the mixed solvent within the above-described range, the yield of the produced pulp can be improved.

According to an exemplary embodiment of the present invention, the forming of the pulp may be performed at a temperature of 100 °C or more and 150 °C or less. Specifically, the temperature in the step of forming the pulp may be 110 °C or more and 140 °C or less, or 120 °C or more and 130 °C or less. By adjusting the temperature at which the step of forming the pulp is performed within the above range, the pulp may be stably formed from the biomass raw material.

In addition, the forming of the pulp may be performed for 60 minutes or more and 180 minutes or less, 90 minutes or more and 160 minutes or less, or 120 minutes or more and 150 minutes or less. When the time for performing the step of forming the pulp is within the above range, the pulp can be stably formed and the yield of the pulp can be improved.

According to an exemplary embodiment of the present invention, in the step of preparing the pulp, pulp may be prepared from the biomass raw material through a chemical pulping method, a mechanical pulping method, or a chemical-mechanical pulping method. In addition, in the step of preparing the pulp, kraft pulp, sulfite pulp, seaweed pulp, and the like may be manufactured using the biomass raw material. In addition, the prepared pulp may be used after being bleached or used without being bleached.

According to an exemplary embodiment of the present invention, the prepared pulp may be washed. Specifically, impurities contained in the pulp may be removed using distilled water. Through this, it is possible to effectively prevent deterioration of physical properties of the biogel to be produced.

According to an exemplary embodiment of the present invention, the preparing of the cellulose fibers may include preparing a pulp slurry by mixing the pulp with a basic solution; and preparing the cellulose microfibers and cellulose fibrils by putting the pulp slurry into a mixer and kneading. That is, by performing the above process, cellulose fibers can be produced from the pulp.

According to an exemplary embodiment of the present invention, the basic solution may include a sodium hydroxide solution, a potassium hydroxide solution, and a lithium hydroxide solution, but the type of the basic solution is not limited.

According to an exemplary embodiment of the present invention, the concentration of the basic solution included in the pulp slurry may be 0.1 N or more and 1 N or less. Specifically, the concentration of the basic solution may be 0.15 N or more and 0.8 N or less, 0.2 N or more and 0.6 N or less, or 0.25 N or more and 0.5 N or less. When the concentration of the basic solution is within the above range, cellulosic fibers may be effectively formed from the pulp slurry.

According to an exemplary embodiment of the present invention, the pH of the pulp slurry may be 8 or more and 14 or less. Specifically, the pH of the pulp slurry may be 9 or more and 13 or less, or 10 or more and 12 or less. Cellulose fibers can be effectively formed from the pulp slurry by adjusting the pH of the pulp slurry to the above range. In addition, when the pH of the pulp slurry is within the above-described range, the swelling of the fibers included in the pulp slurry is accelerated, and finer cellulose fibers can be effectively produced through a kneading process described later.

According to an exemplary embodiment of the present invention, with respect to 100 parts by weight of the pulp slurry, the content of the pulp may be 3 parts by weight or more and 15 parts by weight or less. Specifically, with respect to 100 parts by weight of the pulp slurry, the content of the pulp is 4.5 parts by weight or more and 12.5 parts by weight or less, 5 parts by weight or more and 10 parts by weight or less, 3 parts by weight or more and 10 parts by weight or less, or 7.5 parts by weight or more 15 It may be less than parts by weight. For example, the content of the pulp included in the pulp slurry may be 3% by weight or more and 15% by weight or less.

By adjusting the content of the pulp included in the pulp slurry to the above-described range, friction and dispersion between fibers are efficiently performed during the kneading process using a mixer, so that micronized cellulose fibers can be easily manufactured. On the other hand, if the content of the pulp contained in the pulp slurry is too small, the efficiency of friction between fibers is lowered, making it impossible to easily manufacture micronized cellulose fibers. In addition, when the content of the pulp included in the pulp slurry is too large, the pulp slurry has a high viscosity and is not smoothly kneaded.

According to one embodiment of the present invention, the kneading may be performed at a rotational speed of 100 rpm or more and 600 rpm or less. Specifically, the rotation speed at which the kneading step is performed may be 150 rpm or more and 550 rpm or less, 200 rpm or more and 500 rpm or less, 250 rpm or more and 450 rpm or less, or 300 rpm or more and 400 rpm or less. By adjusting the rotational speed at which the kneading step is performed within the above range, the manufactured cellulose fibers can be formed more stably. The rotational speed may mean the rotational speed of a mixer used in the kneading step.

According to an exemplary embodiment of the present invention, the kneading may be performed at a temperature of 20 °C or more and 35 °C or less. By adjusting the temperature in the kneading step within the above range, it is possible to suppress deformation and damage of the manufactured fiber.

According to one embodiment of the present invention, the manufacturing method of the cellulose fibers may control the physical properties of the cellulose fibers produced by adjusting the kneading time. Specifically, the kneading may be performed for 1 hour or more and 3 hours or less. Through this, it is possible to effectively improve physical properties such as water absorption and water retention of the biogel to be produced.

According to an exemplary embodiment of the present invention, the mixer into which the pulp slurry is introduced is a kneader, and may be a Hobart mixer, a spiral mixer, or a vertical mixer. However, the type of the mixer is not limited, and a known device capable of applying shear force to the pulp slurry may be used.

According to one embodiment of the present invention, the preparing of the cellulose fibers may include preparing the cellulose fibrils by homogenizing the pulp. Specifically, cellulose fibrils may be prepared by homogenizing the aforementioned organic solvent pulp. Through this, cellulose nanofibrils (CNF) or microfibrillated cellulose (MFC) can be prepared. In order to homogenize the pulp, a high-pressure homogenizer or a high-pressure emulsifier used in the art may be used. For example, when the pulp is homogenized using a high-pressure homogenizer, the size, shape, etc. You can control it.

According to an exemplary embodiment of the present invention, the lignin content of the cellulose fibers may be 30% by weight or less. That is, the lignin content of the cellulose microfibers prepared from the pulp may be 30% by weight or less, and the lignin content of the cellulose fibrils prepared from the pulp may be 30% by weight or less. Specifically, the lignin content of the prepared cellulose fibers is 0.1% by weight or more and 30% by weight or less, 1% by weight or more and 28% by weight or less, 5% by weight or more and 25% by weight or less, 10% by weight or more and 22.5% by weight or less, or 15 It may be greater than or equal to 20% by weight and less than or equal to 20% by weight. On the other hand, by removing lignin by bleaching the prepared cellulose fiber, it is possible to form a cellulose fiber having a lignin content of 0% by weight.

When the lignin content of the cellulose fibers is within the above-described range, physical properties such as water absorption rate, initial water absorption rate, and water retention rate of the prepared biogel can be effectively improved.

According to an exemplary embodiment of the present invention, the size of the cellulose fibers may be 0.1 μm or more and 500 μm or less. That is, the size of the cellulose microfibers prepared from the pulp may be 0.1 μm or more and 500 μm or less, and the size of the cellulose fibrils prepared from the pulp may be 0.1 μm or more and 500 μm or less. Specifically, the size of the cellulose fibers is 1 μm or more and 475 μm or less, 5 μm or more and 450 μm or less, 10 μm or more and 400 μm or less, 20 μm or more and 375 μm or less, 30 μm or more and 350 μm or less, 40 μm or more and 320 μm or less. , 0.1 μm or more and 100 μm or less, 10 μm or more and 100 μm or less, 15 μm or more and 97.5 μm or less, 20 μm or more and 95 μm or less, or 25 μm or more and 92.5 μm or less. When the size of the cellulose fibers is within the above-described range, physical properties such as water absorption and water retention of the prepared biogel can be effectively improved. In addition, the size of the cellulose fibers may mean the average size of the particles.

According to one embodiment of the present invention, after the step of preparing the cellulose fibers, the step of replacing the cellulose fibers may be included. Specifically, the hydroxyl group present in the repeating unit of the aforementioned cellulose fiber may be substituted by acetylation or esterification. For example, in the step of substituting the cellulose fibers, an alkali agent, a carboxymethylating agent, and an organic solvent or an organic solvent aqueous solution may be added to the cellulose fibers to form a mixed solvent, followed by a carboxymethylation reaction in the mixed solvent. Through this, carboxymethyl cellulose nanofibrils (CNCNF) or microfibrillated carboxymethyl cellulose (MFMCC) can be prepared. When the cellulose fiber is substituted, the hydroxyl group present in cellulose can be substituted by a substitution reaction, and carboxymethyl prepared by adjusting the content of the alkali agent, carboxymethylating agent, and organic solvent, reaction temperature, reaction time, etc. The degree of substitution (D.S.) of cellulose fibers can be adjusted. For example, when all three hydroxyl groups present in cellulose are substituted, the degree of substitution may have a maximum value of 3, and when only one hydroxyl group is substituted, the degree of substitution may have a value of 1.

According to an exemplary embodiment of the present invention, the cellulose derivative may include at least one of alkyl cellulose, carboxy cellulose, acetyl cellulose, nitro cellulose and hydro cellulose. For example, the cellulose-based derivative may be one in which hydroxyl groups present in repeating units of cellulose are substituted by acetylation or esterification.

Specifically, the alkyl cellulose may include at least one of methyl cellulose (MC), dimethyl cellulose, ethyl cellulose (EC), and methylethyl cellulose. In addition, the carboxy cellulose may include at least one of carboxymethyl cellulose (CMC), carboxymethylethyl cellulose and carboxyethylmethyl cellulose. In addition, the acetyl cellulose may include at least one of cellulose acetate (CA), triacetyl cellulose (TAC), acetylmethyl cellulose, and acetylethyl cellulose. Also, the nitrocellulose may be cellulose nitrate (CN). In addition, the hydrocellulose is at least one of hydroxypropylmethyl cellulose, hydroxyethylmethyl cellulose, hydroxyethyl cellulose, 2-hydroxyethyl cellulose, methyl 2-hydroxyethyl cellulose, hydroxypropyl cellulose and hydroxybutylmethyl cellulose may contain one. When the cellulose raw material includes the above-described cellulose-based derivative, physical properties such as water absorption rate, initial water absorption rate, and water retention rate of the prepared biogel can be effectively improved.

According to an exemplary embodiment of the present invention, a suspension may be prepared by mixing the cellulose raw material and a solvent. Distilled water, water, brine, acetone, ethanol, methanol, etc. may be used as the solvent. When the solvent is used, it is easy to mix with the cellulose raw material, so that the biogel can be effectively prepared.

According to an exemplary embodiment of the present invention, the solvent may be saline. Specifically, the brine may be the same as or different from the brine used in the post-treatment process, and may include the same or different salt from the salt used in the post-treatment process. More specifically, the brine may include the same or different salt as the salt added in the step of immersion, washing, or preparing the cellulose gel mixture, and the brine may be the same as the brine used in the post-treatment step, or When the same salt is included, physical properties such as water absorption rate of the biogel produced may be better, and dehydration and drying efficiency of the biogel may be better.

According to an exemplary embodiment of the present invention, the cellulose raw material may include at least one of a cellulose derivative and the cellulose fiber. Specifically, the cellulose raw material may include the cellulose derivative and the cellulose fiber. In the case of preparing a suspension including the cellulose raw material, the biogel produced is biodegradable, so it is environmentally friendly and has excellent water retention.

According to an exemplary embodiment of the present invention, the weight ratio of the cellulose derivative and the cellulose fibers included in the cellulose raw material may be 10:1 to 1:10. Specifically, the weight ratio of the cellulose derivative to the cellulose fibers may be 7:1 to 1:7, 5:1 to 1:5, or 3:1 to 1:3. When the weight ratio of the cellulose derivative to the cellulose fiber is within the above-described range, physical properties such as water absorption rate and water retention rate of the prepared biogel can be effectively improved.

According to an exemplary embodiment of the present invention, the content of the cellulose raw material may be 1 part by weight or more and 10 parts by weight or less based on 100 parts by weight of the cellulose suspension. Specifically, the content of the cellulose fibers included in the suspension is 1 part by weight or more and 7 parts by weight or less, 1 part by weight or more and 5 parts by weight or less, 1 part by weight or more and 3 parts by weight or less, 3 parts by weight or more based on 100 parts by weight of the suspension. It may be 10 parts by weight or more, 3 parts by weight or more and 7 parts by weight or less, 3 parts by weight or more and 5 parts by weight or less, or 2.5 parts by weight or more and 4.5 parts by weight or less. By adjusting the content of the cellulose raw material included in the suspension within the above range, the biogel can be effectively prepared, and physical properties such as water absorption and water retention can be effectively improved.

According to an exemplary embodiment of the present invention, preparing the cellulose gel may include adding an acrylic monomer, a polymerization initiator, and a crosslinking agent to the cellulose suspension. Specifically, the acrylic monomer may include at least one of an acrylic acid-based monomer, an acrylic ester-based monomer, and an acrylamide-based monomer.

More specifically, the acrylic acid-based monomers include acrylic acid, methacrylic acid, 2-(meth)acryloyloxy acetic acid, 3-(meth)acryloyloxy propyl acid, 4-(meth)acryloyloxy butyric acid, It may include at least one of itaconic acid and maleic acid. In addition, the acrylic ester monomers include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, 2-ethylhexyl acrylate, butyl methacrylate, 2-ethylhexyl methacrylate, decyl acrylate, It may contain at least one of ethylene vinyl acetate, isobornyl acrylate and isobornyl methacrylate. In addition, the acrylamide-based monomer may include at least one of acrylol morpholine, N,N-diethyl acrylamide, and N,N-dimethyl acrylamide (DMAA). there is. In the case of including the above-described acrylic monomer, the biogel can be effectively prepared, and physical properties such as water absorption and water retention of the biogel can be effectively improved.

According to an exemplary embodiment of the present invention, the content of the acrylic monomer may be 5 parts by weight or more and 15 parts by weight or less based on 100 parts by weight of the cellulose suspension. Specifically, the content of the acrylic monomer is 5 parts by weight or more and 12.5 parts by weight or less, 5 parts by weight or more and 10 parts by weight or less, 7.5 parts by weight or more and 15 parts by weight or less, 10 parts by weight or more and 15 parts by weight or more, based on 100 parts by weight of the cellulose suspension. parts by weight or less or 7.5 parts by weight or more and 12.5 parts by weight or less. When the content of the acrylic monomer is within the above range, the gelation degree and crosslinking reaction of the prepared biogel can be maintained at an appropriate level, and thus the physical properties such as water absorption and water retention of the prepared biogel can be effectively improved. there is.

According to an exemplary embodiment of the present invention, the polymerization initiator may include at least one of potassium persulfate, sodium sulfate and ammonium persulfate. In the case of including the aforementioned polymerization initiator, the bio-gel can be effectively prepared.

According to an exemplary embodiment of the present invention, the content of the polymerization initiator may be 0.1 parts by weight or more and 5 parts by weight or less based on 100 parts by weight of the cellulose suspension. Specifically, the content of the polymerization initiator may be 0.1 parts by weight or more and 3 parts by weight or less, 0.1 parts by weight or more and 2 parts by weight or less, or 0.1 parts by weight or more and 1 part by weight or less, based on 100 parts by weight of the cellulose suspension. When the content of the polymerization initiator is within the above range, the crosslinking reaction between the cellulose fibers may be promoted. In addition, by using the polymerization initiator, the crosslinking reaction time can be shortened and the temperature at which the crosslinking reaction is performed can be lowered, so that the biogel can be effectively prepared.

According to an exemplary embodiment of the present invention, the crosslinking agent may include any one of an epoxy-based compound, an aldehyde-based compound, and an acrylamide-based compound. In the case of including the aforementioned crosslinking agent, crosslinking between the cellulose fibers can be effectively formed. As a result, the bio-gel can be gelled when immersed in water to form a structure that stably retains water.

According to an exemplary embodiment of the present invention, the crosslinking agent may include an epoxy-based compound. Specifically, the epoxy-based compound is epichlorohydrin, glycerol diglycidyl ether, glycerol polyglycidyl ether, diglycerol polyglycidyl ether, polyglycerol polyglycidyl ether, ethylene glycol diglycidyl ether , diethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, dipropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, resorcinol diglycidyl Cydyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, polybutadiene diglycidyl ether, trimethylolpropane polyglycidyl ether , sorbitol polyglycidyl ether or pentaerythritol polyglycidyl ether. By using an epoxy-based compound as the crosslinking agent, crosslinking between the cellulose fibers can be effectively formed. In addition, when an epoxy-based compound is used as a crosslinking agent, the prepared biogel can stably maintain its shape without dissociation in water even when immersed in water.

According to an exemplary embodiment of the present invention, the crosslinking agent may include an aldehyde-based compound. Specifically, the aldehyde-based compound is glutaraldehyde, formaldehyde, dialdehyde starch, succinic aldehyde, acrylaldehyde, oxalaldehyde, 2-methylacrylaldehyde, 2-oxopropanal, dextrin aldehyde, greeoxal, succinic aldehyde and at least one of diphaldehyde. By using an aldehyde-based compound as the crosslinking agent, crosslinking between the cellulose fibers can be effectively formed, thereby stably forming a biogel. Through this, it is possible to effectively improve physical properties such as water absorption and water retention of the biogel to be produced.

According to an exemplary embodiment of the present invention, the crosslinking agent may include an acrylamide-based compound. Specifically, the acrylamide-based compound may be any multifunctional acrylamide-based compound having a bifunctional or more functional acrylamide group. More specifically, the acrylamide-based compound is N,N'-ethylene bisacrylamide, N,N'-hexamethylenebisacrylamide, N,N'-hexamethylenebisacrylamide, N, N'-methylene bisacrylamide (N,N'-Methylenebisacrylamide), N,N'-cystamine bisacrylamide (N,N'-Cystaminebisacrylamide), and N,N'-diallylacrylamide (N,N- Diallylacrylamide) may include at least one. By using an acrylamide-based compound as the crosslinking agent, crosslinking between the cellulose fibers can be effectively formed, thereby stably forming a biogel. Through this, it is possible to effectively improve physical properties such as water absorption and water retention of the biogel to be produced.

According to an exemplary embodiment of the present invention, the content of the crosslinking agent may be 0.1 parts by weight or more and 5 parts by weight or less based on 100 parts by weight of the cellulose suspension. Specifically, the amount of the crosslinking agent may be 0.1 part by weight or more and 3 parts by weight or less, 0.1 part by weight or more and 2 parts by weight or less, or 0.1 part by weight or more and 1 part by weight or less, based on 100 parts by weight of the cellulose suspension. When the content of the crosslinking agent is within the above range, the biogel can be effectively prepared.

According to an exemplary embodiment of the present invention, the step of preparing the cellulose gel may be performed at a temperature of 50 °C or more and 80 °C or less for 30 minutes to 3 hours. Specifically, the step of preparing the cellulose gel may be performed at a temperature of 50 °C or more and 75 °C or less, 55 °C or more and 80 °C or less, or 60 °C or more and 70 °C or less. In addition, the step of preparing the cellulose gel may be performed for 1 hour to 3 hours, 1 hour to 2 hours, 1 hour to 1 hour 30 minutes, or 1 hour 30 minutes to 2 hours. By adjusting the temperature and time for preparing the cellulose gel within the above-described range, the bio-gel may be stably prepared from the suspension.

According to an exemplary embodiment of the present invention, immersing the cellulose gel in water or saline; may be performed for 1 hour or more and 24 hours or less. Specifically, immersing the cellulose gel in water or saline; is 1 hour or more and 18 hours or less, 1 hour or more and 12 hours or less, 6 hours or more and 24 hours or less, 12 hours or more and 24 hours or less, or 6 hours or more and 18 hours or less It may be performed during the time of By adjusting the immersion time of the cellulose gel within the above range, dehydration and drying of the biogel can be more easily performed, and the drying time of the gel can be shortened without using a separate organic solvent in the post-treatment process, thereby achieving economic feasibility and safety. can increase

According to an exemplary embodiment of the present invention, immersing the cellulose gel in water or saline; may include mixing the water or saline and the cellulose gel at a weight ratio of 5:1 or more and 20:1 or less. Specifically, the step of immersing the cellulose gel in water or saline; the water or saline and the cellulose gel in a ratio of 5:1 or more to 19:1 or less, 5:1 or more to 18:1 or less, 5:1 or more to 17:1 5:1 or more 16:1 or less, 6:1 or more 20:1 or less, 7:1 or more 20:1 or less, 8:1 or more 20:1 or less, 9:1 or more 20:1 or less, 10:1 It may be mixed in a weight ratio of 20:1 or less, 7:1 or more and 18:1 or less, or 9:1 or more and 16:1 or less. By adjusting the mixing ratio within the above range, dehydration and drying of the biogel can be more easily performed, and the drying time of the gel can be shortened without using a separate organic solvent in the post-treatment process, thereby improving economic feasibility and safety.

According to an exemplary embodiment of the present invention, the brine may contain the salt. Specifically, the saline may include the same or different salt as the salt added in the step of preparing the suspension or preparing the cellulose gel mixture, and the saline is added in the step of preparing the suspension, washing, or preparing the cellulose gel mixture In the case of including the same salt as the salt, the efficiency of dehydration and drying of the biogel may be better.

According to one embodiment of the present invention, washing the immersed cellulose gel; may include. Specifically, the washing may be to remove impurities from the immersed cellulose gel using water or saline. The washing may be repeated several times, for example, the washing may be performed 1 to 5 times with water or saline. In the case of performing the washing under the above-mentioned conditions, physical properties such as water absorption rate and water holding capacity of the prepared biogel may be more excellent.

According to one embodiment of the present invention, the saline may be the same as or different from the saline used in the suspension preparation or post-treatment process, and may include the same or different salt from the salt used in the post-treatment process. More specifically, the brine may include the same or different salts as those added in the step of preparing the suspension, immersion, or preparing the cellulose gel mixture. When the brine is the same as the brine used for suspension preparation or immersion, or contains the same salt as the salt, impurities can be easily removed, and the biogel produced can have better physical properties and better dehydration and drying efficiency. can

According to a temporary state of the present invention, preparing a cellulose gel mixture by mixing and homogenizing a salt in the washed cellulose gel; may include.

According to an exemplary embodiment of the present invention, the salt may include at least one of sodium chloride, potassium chloride, calcium chloride and magnesium chloride. For example, the salt may be sodium chloride. In the case of using the above-mentioned type of salt, the salt induces rapid dehydration of the biogel, so that the drying time of the biogel can be further shortened.

According to an exemplary embodiment of the present invention, the amount of the salt may be 0.5 parts by weight or more and 30 parts by weight or less based on 100 parts by weight of the total weight of the washed cellulose gel and the salt. Specifically, based on 100 parts by weight of the total weight of the washed cellulose gel and the salt, the salt content is 0.5 parts by weight or more and 25 parts by weight or less, 0.5 parts by weight or more and 20 parts by weight or less, 0.5 parts by weight or more and 15 parts by weight or less, 0.5 parts by weight or more and 10 parts by weight or less, 0.5 parts by weight or more and 7 parts by weight or less, 1 part by weight or more and 30 parts by weight or less, 2 parts by weight or more and 30 parts by weight or less, 4 parts by weight or more and 30 parts by weight or less, 7 parts by weight or more 30 It may be 1 part by weight or more and 20 parts by weight or less, or 2 parts by weight or more and 10 parts by weight or less. When the content of the salt satisfies the aforementioned range, the rate of water absorption and water retention are reduced during the dehydration process of the biogel, leading to rapid dehydration of the biogel and shortening the drying time of the biogel. In addition, the prepared biogel may have an appropriate water absorption rate to be applied to a hygroscopic material.

According to an exemplary embodiment of the present invention, preparing the cellulose gel mixture by mixing and homogenizing the washed cellulose gel with a salt; may be performed at a rotational speed of 100 rpm or more and 1000 rpm or less. Specifically, the rotation speed at which the step of preparing the cellulose gel mixture is performed is 200 rpm or more and 1000 rpm or less, 400 rpm or more and 1000 rpm or less, 600 rpm or more and 1000 rpm or less, 800 rpm or more and 1000 rpm or less, or 800 rpm or more 1000 rpm or less. By adjusting the rotational speed at which the preparing of the cellulose gel mixture is performed within the above-described range, the prepared cellulose gel mixture is effectively homogenized and drying of the biogel may be more easily performed.

According to an exemplary embodiment of the present invention, the particle size of the cellulose gel mixture may be 0.1 mm or more and 1 cm or less. When the particle size of the cellulose gel mixture satisfies the aforementioned range, the particle size of the biogel may be more easily controlled through the pulverization process described later, and the physical properties of the produced biogel may be better.

According to an exemplary embodiment of the present invention, mixing the washed cellulose gel with a salt and homogenizing to prepare the cellulose gel mixture; mixing the homogenized cellulose gel with polar group-containing cellulose; may further include there is. Specifically, in the process of preparing a cellulose gel mixture by adding and mixing the salt to the washed cellulose gel and then homogenizing it, polar group-containing cellulose may be additionally mixed in order to further improve the physical properties of the biogel.

According to an exemplary embodiment of the present invention, the polar group-containing cellulose may include at least one of a carboxyl group-containing cellulose, an acetyl group-containing cellulose, a nitro group-containing cellulose, and a hydroxyl group-containing cellulose. More specifically, the carboxyl group-containing cellulose may include at least one of carboxymethyl cellulose (CMC), carboxymethylethyl cellulose, and carboxyethylmethyl cellulose. In addition, the acetyl group-containing cellulose may include at least one of cellulose acetate (CA), triacetyl cellulose (TAC), acetylmethyl cellulose, and acetylethyl cellulose. In addition, the nitro group-containing cellulose may be cellulose nitrate (CN). In addition, the hydroxy group-containing cellulose includes hydroxypropylmethyl cellulose, hydroxyethylmethyl cellulose, hydroxyethyl cellulose, 2-hydroxyethyl cellulose, methyl 2-hydroxyethyl cellulose, hydroxypropyl cellulose and hydroxybutylmethyl It may contain at least one of cellulose. When the polar group-containing cellulose is mixed, physical properties such as water absorption rate, initial water absorption rate, and water retention rate of the prepared biogel can be effectively improved.

According to an exemplary embodiment of the present invention, preparing a cellulose gel mixture by mixing the homogenized cellulose gel and the polar group-containing cellulose; 5 parts by weight of the polar group-containing cellulose with respect to 100 parts by weight of the homogenized cellulose gel It may be to mix more than 30 parts by weight or less. Specifically, based on 100 parts by weight of the total dry weight of the homogenized cellulose gel, the polar group-containing cellulose may be mixed in an amount of 5 parts by weight or more and 30 parts by weight or less. By adjusting the content of the polar group-containing cellulose within the above-described range, the prepared biogel can be stably formed, and physical properties such as water absorption and water retention of the prepared biogel can be effectively improved.

According to an exemplary embodiment of the present invention, the mixing of the homogenized cellulose gel and the polar group-containing cellulose; may be performed at a rotational speed of 100 rpm or more and 1000 rpm or less. Specifically, mixing the homogenized cellulose gel and the polar group-containing cellulose; the rotational speed at which this is performed is 200 rpm or more and 1000 rpm or less, 400 rpm or more and 1000 rpm or less, 600 rpm or more and 1000 rpm or less, 800 rpm or more and 1000 rpm or less , or 800 rpm or more and 1000 rpm or less. When the rotational speed at which the mixing of the homogenized cellulose gel and the polar group-containing cellulose is performed is adjusted within the above-mentioned range, the produced bio-gel may have better physical properties.

According to an exemplary embodiment of the present invention, preparing a bio-gel by dehydrating, drying and pulverizing the cellulose gel mixture; may further include. Specifically, by including the steps of dehydration, drying, and grinding, the biogel can be prepared by removing the solvent from the mixture, and the water absorption rate and water retention of the biogel can be effectively improved.

According to an exemplary embodiment of the present invention, the step of dehydrating the mixture may be performed by a method of vacuum filtration, gravity filtration, compression filtration, or vacuum filtration. Through the dehydrating step, the solvent contained in the biogel can be effectively removed in the subsequent drying step, so that the drying efficiency is improved and the time and cost of preparing the biogel can be further reduced.

According to an exemplary embodiment of the present invention, drying the cellulose gel mixture may be performed by hot air drying, reduced pressure drying, or natural drying. By drying by the method of hot air drying, reduced pressure drying, or natural drying, the finally produced biogel does not re-aggregate after drying, so it can have excellent water absorption rate and initial water absorption rate.

According to an exemplary embodiment of the present invention, the step of drying the cellulose gel mixture may be performed at a temperature of 40 °C or more and less than 100 °C. When the temperature range of the drying is within the above-mentioned range, it is possible to prevent heat-induced damage to the prepared biogel, and the biogel can be efficiently produced.

According to an exemplary embodiment of the present invention, the step of grinding the cellulose gel mixture may be to adjust the particle size of the dried cellulose gel mixture to a diameter of 0.1 mm or more and 1.0 mm or less. Specifically, the pulverization reduces the particle size of the dried cellulose gel mixture to a diameter of 0.1 mm or more and 0.7 mm or less, 0.1 mm or more and 0.7 mm or less, 0.1 mm or more and 0.6 mm or less, 0.1 mm or more and 0.5 mm or less, 0.3 mm or more and 1.0 mm or more. Or less, it may be adjusted to 0.5 mm or more and 1.0 mm or less or 0.3 mm or more and 0.7 mm or less. When the particle size of the dried cellulose gel mixture is adjusted within the above-described range, the water absorption rate and water retention rate of the prepared biogel can be effectively improved. In addition, the grinding may be performed by a conventional method such as grinding using a grinder.

According to an exemplary embodiment of the present invention, preparing the bio-gel; may further include washing the dehydrated cellulose gel mixture with an organic solvent. Specifically, the step of preparing the biogel; is washed with water or brine to dehydrate the water inside the gel, and then additionally washed using an organic solvent in the washing and drying process, such as the water absorption rate and water retention of the biogel It may be to further improve the physical properties of.

According to an exemplary embodiment of the present invention, the organic solvent may be alcohol having a carbon number of 1 or more and 3 or less, for example, ethanol. In the case of using the organic solvent of the above-mentioned type, the physical properties of the prepared bio-gel may be more excellent.

According to an exemplary embodiment of the present invention, the organic solvent may be mixed with the dehydrated cellulose gel mixture in a weight ratio of 1:1 or more and 5:1 or less. Specifically, the organic solvent is 1: 1 or more 4: 1 or less, 1: 1 or more 3: 1 or less, 2: 1 or more 5: 1 or less, 3: 1 or more 5: 1 or less with the dehydrated cellulose gel mixture It may be mixed in a weight ratio of 2:1 or more and 4:1 or less. When the weight ratio of the organic solvent and the dehydrated cellulose gel mixture satisfies the above range, the physical properties of the biogel produced are better, and the organic solvent is used 50 times or more in the washing and drying process of the biogel Existing process Since only a small amount of organic solvent is used compared to the above, economic feasibility and safety may be excellent.

One embodiment of the present invention provides a bio-gel prepared by the above manufacturing method.

Biogel according to an exemplary embodiment of the present invention may have excellent biodegradability, water absorption rate, and water retention.

According to an exemplary embodiment of the present invention, the water absorption rate of the biogel may be 1,000% or more and 5,000% or less. Specifically, the water absorption rate of the biogel may be 1,000% or more, 1,300% or more, 1,500% or more, 1,700% or more, or 2,000% or more. Specifically, the water absorption rate of the biogel may be 5,000% or less, 4,500% or less, 4,000% or less, or 3,500% or less. The bio-gel that satisfies the water absorption rate in the above range can be effectively applied to an absorbent article.

According to an exemplary embodiment of the present invention, the water absorption rate of the biogel may be the absorption rate of the biogel to saline solution. Specifically, the biogel may have excellent absorption rates for both distilled water and saline, and the absorption rate for distilled water may be higher than that of the biogel for saline.

According to an exemplary embodiment of the present invention, the water retention per 1 g of the bio-gel may be 10 g or more. Specifically, the water retention per 1 g of the biogel is 10 g or more and 300 g or less, 10 g or more and 250 g or less, 10 g or more and 200 g or less, 10 g or more and 150 g or less, 10 g or more and 100 g or less, 30 g or more 300 g or less, 50 g or more and 300 g or less, 100 g or more and 300 g or less, or 70 g or more and 250 g or less. The biogel that satisfies the water retention in the above range can be effectively applied to an absorbent article.

According to an exemplary embodiment of the present invention, the biogel may be a cellulose-based porous material, and the cellulose-based porous material may be formed in the form of airgel, xerogel, or cryogel. there is.

According to an exemplary embodiment of the present invention, the biogel can be used for sanitary products such as diapers for infants and adults and sanitary napkins for women, as well as agricultural soil moisture regulators, absorbent pads and ice packs for food packaging, medical hydropatch, and the like, and is biodegradable. Since it has properties, it is possible to reduce serious environmental pollution occurring in the process of incineration and landfill of non-degradable absorbent articles.

An exemplary embodiment of the present invention provides an absorbent article comprising an absorbent structure comprising biogel manufactured by the above manufacturing method. An absorbent article according to an exemplary embodiment of the present invention is environmentally friendly and has advantages of being non-toxic and biodegradable.

According to an exemplary embodiment of the present invention, the absorbent structure may be manufactured by compressing the biogel to prepare a plurality of absorbent layers, and bonding the prepared plurality of absorbent layers to each other. In this case, as a method of compressing the biogel, a compressor or the like used in the art may be used.

According to an exemplary embodiment of the present invention, the water absorption rate of the absorbent structure may be 10 times or more and 30 times or less compared to its own weight. Specifically, the water absorption rate of the absorbent structure may be 10 times or more and 25 times or less, 10 times or more and 20 times or less, 15 times or more and 30 times or less, 20 times or more and 30 times or less, or 15 times or more and 25 times or less compared to their own weight. there is. When the absorbent structure has a water absorption rate within the aforementioned range, the water absorption rate and water retention capacity of the absorbent article including the absorbent structure may be excellent.

According to an exemplary embodiment of the present invention, the water absorption rate of the absorbent structure may be the absorption rate of the absorbent structure for saline water. Specifically, the absorbent structure may have excellent water absorption rates for distilled water and saline water, and the water absorption rate for distilled water may be higher than that of the absorbent structure for saline water.

According to an exemplary embodiment of the present invention, the absorbent article may include at least one of a sanitary product, a soil moisture regulator, an absorbent pad, an ice pack, and a hydro patch. Specifically, the absorbent article may include at least one of sanitary products such as diapers for infants and adults, sanitary pads for women, soil moisture regulators for agriculture or horticulture, absorbent pads for food packaging, ice packs, and medical hydro patches. Since the absorbent article of the above-described type includes the absorbent structure including the biogel, it has an excellent water absorption rate and biodegradability, so it can reduce environmental pollution generated in the process of incineration and landfill, and thus can be environmentally friendly.

Hereinafter, examples will be described in detail to explain the present invention in detail. However, embodiments according to the present invention can be modified in many different forms, and the scope of the present invention is not construed as being limited to the embodiments described below. The embodiments herein are provided to more completely explain the present invention to those skilled in the art.

Example: Preparation of biogel

Example 1

Example 1-1

A cellulose suspension was prepared by mixing carboxymethyl cellulose having a degree of substitution of 0.8 with distilled water as a cellulose raw material. At this time, based on 100 parts by weight of the suspension, the content of carboxymethyl cellulose was 3 parts by weight.

Thereafter, acrylic acid (AA, Acrylic acid, Guaranteed, DAEJUNG Chemicals & Metals co. Ltd., Korea) as an acrylic monomer and potassium persulfate (K, Potassium persulfate 99.0%, Special grade, SAMJUNG Chemicals co. Ltd., SAMJUNG Chemicals co. Ltd. ., Korea) and N, N'-methylenebisacrylamide (MBA, N, N'-methylenebisacrylamide, Alfa Aesar) as a crosslinking agent were added in turn. At this time, based on 100 parts by weight of the suspension, the content of acrylic acid was 7 parts by weight, the content of potassium persulfate was 0.4 parts by weight, and the content of N, N'-methylenebisacrylamide was 0.2 parts by weight.

Thereafter, the mixture of acrylic acid, potassium persulfate, and N, N'-methylenebisacrylamide was stirred for 10 minutes at 600 rpm using a stirrer, and at a temperature of 70 ° C. for 1 hour and 30 minutes with stirring stopped. reacted After the reaction, the resulting cellulose gel was soaked in distilled water for 18 hours. At this time, the mixing ratio of the distilled water used for the immersion was 2000 parts by weight based on 100 parts by weight of the cellulose gel.

Thereafter, it was filtered through a 200 mesh net, washed three to four times with distilled water, and sodium chloride (NaCl, Sodium chloride) was added as a salt to the washed cellulose gel, followed by homogenization at 800 rpm for 10 minutes to prepare a cellulose gel mixture. . At this time, the content of sodium chloride was adjusted to 0.9 parts by weight based on 100 parts by weight of the total weight of the washed cellulose gel and the sodium chloride, and the particle size of the cellulose gel mixture was adjusted to a diameter of 0.1 mm or more and 1.0 cm or less.

Then, after dehydrating the cellulose gel mixture, the sample was dried in an oven (JSOP-100, JS Research Inc., Korea) at 50 ° C. to completely remove the solution that was not partially removed, and then pulverized to obtain a particle size of 1.0 mm or less. A biogel was prepared.

Example 1-2

In Example 1-1, the same method as in Example 1-1, except that the amount of sodium chloride added as a salt was adjusted to 2.0 parts by weight based on 100 parts by weight of the total weight of the washed cellulose gel and the sodium chloride. A biogel was prepared.

Examples 1-3

In Example 1-1, the same method as in Example 1-1, except that the amount of sodium chloride added as a salt was adjusted to 4.0 parts by weight based on 100 parts by weight of the total weight of the washed cellulose gel and the sodium chloride. A biogel was prepared.

Example 1-4

In Example 1-1, the same method as in Example 1-1, except that the amount of sodium chloride added as a salt was adjusted to 7.0 parts by weight based on 100 parts by weight of the total weight of the washed cellulose gel and the sodium chloride. A biogel was prepared.

Example 1-5

In Example 1-1, the same method as in Example 1-1, except that the amount of sodium chloride added as a salt was adjusted to 10.0 parts by weight based on 100 parts by weight of the total weight of the washed cellulose gel and the sodium chloride. A biogel was prepared.

Example 1-6

In Example 1-1, the same method as in Example 1-1, except that the amount of sodium chloride added as a salt was adjusted to 20.0 parts by weight based on 100 parts by weight of the total weight of the washed cellulose gel and the sodium chloride. A biogel was prepared.

Example 2

Example 2-1

In Example 1-1, the cellulose gel produced after the reaction was immersed in 2000 parts by weight of 0.9% sodium chloride aqueous solution based on 100 parts by weight of the cellulose gel for 18 hours, and then 3 to 200 mesh with 0.9% sodium chloride aqueous solution. A biogel was prepared in the same manner as in Example 1-1, except for repeated washing 4 times.

Example 2-2

In Example 1-2, the cellulose gel produced after the reaction was immersed in 2000 parts by weight of 0.9% sodium chloride aqueous solution based on 100 parts by weight of the cellulose gel for 18 hours, and then 3 to 200 mesh with 0.9% sodium chloride aqueous solution. A biogel was prepared in the same manner as in Example 1-2, except that it was repeatedly washed 4 times.

Example 2-3

In Example 1-3, the cellulose gel produced after the reaction was immersed in 2000 parts by weight of 0.9% sodium chloride aqueous solution based on 100 parts by weight of the cellulose gel for 18 hours, and then 3 to 200 mesh with 0.9% sodium chloride aqueous solution. A biogel was prepared in the same manner as in Examples 1-3, except that it was repeatedly washed 4 times.

Example 2-4

In Example 1-4, the cellulose gel produced after the reaction was immersed in 2000 parts by weight of a 0.9% sodium chloride aqueous solution based on 100 parts by weight of the cellulose gel for 18 hours, and then 3 to 200 mesh with 0.9% sodium chloride aqueous solution. A biogel was prepared in the same manner as in Examples 1-4, except that it was repeatedly washed 4 times.

Example 2-5

In Example 1-5, the cellulose gel produced after the reaction was immersed in 2000 parts by weight of 0.9% sodium chloride aqueous solution based on 100 parts by weight of the cellulose gel for 18 hours, and then 3 to 200 mesh with 0.9% sodium chloride aqueous solution. A biogel was prepared in the same manner as in Examples 1-5, except that it was repeatedly washed 4 times.

Example 2-6

In Example 1-6, the cellulose gel produced after the reaction was immersed in 2000 parts by weight of 0.9% sodium chloride aqueous solution based on 100 parts by weight of the cellulose gel for 18 hours, and then 3 to 200 mesh with 0.9% sodium chloride aqueous solution. A biogel was prepared in the same manner as in Examples 1-6, except that it was repeatedly washed 4 times.

Example 3

Example 3-1

In Example 2-1, 30 parts by weight of carboxymethyl cellulose (CMC powder, Carboxymethyl cellulose) having a degree of substitution of 0.8 as polar group-containing cellulose was added to the homogenized cellulose gel, based on 100 parts by weight of the homogenized cellulose gel, , A biogel was prepared in the same manner as in Example 2-1, except that the cellulose gel mixture was prepared by stirring at 800 rpm for 10 minutes.

Example 3-2

In Example 2-2, 30 parts by weight of carboxymethyl cellulose having a degree of substitution of 0.8 as polar group-containing cellulose was added to the homogenized cellulose gel based on 100 parts by weight of the homogenized cellulose gel, and at 800 rpm for 10 minutes Biogel was prepared in the same manner as in Example 2-2, except that the cellulose gel mixture was prepared by stirring.

Example 3-3

In Example 2-3, 30 parts by weight of carboxymethyl cellulose having a degree of substitution of 0.8 as a polar group-containing cellulose was added to the homogenized cellulose gel based on 100 parts by weight of the homogenized cellulose gel, and at 800 rpm for 10 minutes Biogel was prepared in the same manner as in Example 2-3, except that the cellulose gel mixture was prepared by stirring.

Example 3-4

In Examples 2-4, 30 parts by weight of carboxymethyl cellulose having a degree of substitution of 0.8 as polar group-containing cellulose was added to the homogenized cellulose gel based on 100 parts by weight of the homogenized cellulose gel, and at 800 rpm for 10 minutes Biogel was prepared in the same manner as in Examples 2-4, except that the cellulose gel mixture was prepared by stirring.

Example 3-5

In Example 2-5, 30 parts by weight of carboxymethyl cellulose having a degree of substitution of 0.8 as polar group-containing cellulose was added to the homogenized cellulose gel based on 100 parts by weight of the homogenized cellulose gel, and at 800 rpm for 10 minutes Biogel was prepared in the same manner as in Examples 2-5, except that the cellulose gel mixture was prepared by stirring.

Example 3-6

In Example 2-6, 30 parts by weight of carboxymethyl cellulose having a degree of substitution of 0.8 as a polar group-containing cellulose was added to the homogenized cellulose gel based on 100 parts by weight of the homogenized cellulose gel, and at 800 rpm for 10 minutes Biogel was prepared in the same manner as in Examples 2-6, except that the cellulose gel mixture was prepared by stirring.

Example 4

Example 4-1

In Example 2-5, biogel was prepared in the same manner as in Example 2-5, except that the dehydrated cellulose gel mixture was additionally washed by adding ethanol (99.9%) as an organic solvent. At this time, the content of ethanol was adjusted to 100 parts by weight based on 100 parts by weight of the dehydrated cellulose gel mixture.

Example 4-2

In Example 4-1, with respect to 100 parts by weight of the dehydrated cellulose gel mixture, the content of ethanol was adjusted to 200 parts by weight and additionally washed, and the biogel was prepared in the same manner as in Example 4-1 did

Example 4-3

In Example 4-1, with respect to 100 parts by weight of the dehydrated cellulose gel mixture, the content of ethanol was adjusted to 300 parts by weight and additional washing was performed, and biogel was prepared in the same manner as in Example 4-1. did

Example 5

Example 5-1

In Example 4-1, 30 parts by weight of carboxymethyl cellulose having a degree of substitution of 0.8 as a polar group-containing cellulose was added to the homogenized cellulose gel based on 100 parts by weight of the homogenized cellulose gel, and at 800 rpm for 10 minutes A biogel was prepared in the same manner as in Example 4-1, except that the cellulose gel mixture was prepared by stirring.

Example 5-2

In Example 4-2, 30 parts by weight of carboxymethyl cellulose having a degree of substitution of 0.8 as a polar group-containing cellulose was added to the homogenized cellulose gel based on 100 parts by weight of the homogenized cellulose gel, and at 800 rpm for 10 minutes Biogel was prepared in the same manner as in Example 4-2, except that the cellulose gel mixture was prepared by stirring.

Example 5-3

In Example 4-3, 30 parts by weight of carboxymethyl cellulose having a degree of substitution of 0.8 as polar group-containing cellulose was added to the homogenized cellulose gel, based on 100 parts by weight of the homogenized cellulose gel, and 800 rpm for 10 minutes Biogel was prepared in the same manner as in Example 4-3, except that the cellulose gel mixture was prepared by stirring.

Comparative Example 1

In Example 1-1, the biogel was prepared in the same manner as in Example 1-1, except that the washed cellulose gel was homogenized at 800 rpm for 10 minutes without adding sodium chloride as a salt to prepare a cellulose gel mixture. was manufactured.

Comparative Example 2

In Comparative Example 1, 30 parts by weight of carboxymethyl cellulose having a degree of substitution of 0.8 as polar group-containing cellulose was added to the homogenized cellulose gel based on 100 parts by weight of the homogenized cellulose gel, and stirred at 800 rpm for 10 minutes A biogel was prepared in the same manner as in Comparative Example 1, except that the cellulose gel mixture was prepared.

Comparative Example 3

In Example 1-1, the cellulose gel produced after the reaction was immersed in 2000 parts by weight of ethanol based on 100 parts by weight of the cellulose gel for 24 hours, filtered through a 200 mesh mesh, and repeated 3 to 4 times with excess ethanol. A biogel was prepared in the same manner as in Example 1-1, except that the washed cellulose gel was homogenized at 800 rpm for 10 minutes without adding sodium chloride as a salt to the washed cellulose gel to prepare a cellulose gel mixture.

Comparative Example 4

In Comparative Example 3, 30 parts by weight of carboxymethyl cellulose having a degree of substitution of 0.8 as polar group-containing cellulose was added to the homogenized cellulose gel based on 100 parts by weight of the homogenized cellulose gel, and stirred at 800 rpm for 10 minutes A biogel was prepared in the same manner as in Comparative Example 3, except that the cellulose gel mixture was prepared.

Experimental conditions of Examples 1 to 5 and Comparative Examples 1 to 4 are summarized and shown in Table 1 below.

immersion wash salt added CMC added extra wash Example 1-1 Distilled water Distilled water 0.9 parts by weight NaCl - - Example 1-2 2.0 parts by weight NaCl Example 1-3 4.0 parts by weight NaCl Example 1-4 7.0 parts by weight NaCl Example 1-5 10.0 parts by weight NaCl Example 1-6 20.0 parts by weight NaCl Example 2-1 0.9% NaCl 0.9% NaCl 0.9 parts by weight NaCl - - Example 2-2 2.0 parts by weight NaCl Example 2-3 4.0 parts by weight NaCl Example 2-4 7.0 parts by weight NaCl Example 2-5 10.0 parts by weight NaCl Example 2-6 20.0 parts by weight NaCl Example 3-1 0.9% NaCl 0.9% NaCl 0.9 parts by weight NaCl 30 parts by weight - Example 3-2 2.0 parts by weight NaCl Example 3-3 4.0 parts by weight NaCl Example 3-4 7.0 parts by weight NaCl Example 3-5 10.0 parts by weight NaCl Example 3-6 20.0 parts by weight NaCl Example 4-1 0.9% NaCl 0.9% NaCl 10.0 parts by weight NaCl - 100 parts EtOH Example 4-2 200 parts by weight EtOH Example 4-3 300 parts by weight EtOH Example 5-1 0.9% NaCl 0.9% NaCl 10.0 parts by weight NaCl 30 parts by weight 100 parts EtOH Example 5-2 200 parts by weight EtOH Example 5-3 300 parts by weight EtOH Comparative Example 1 Distilled water Distilled water - - - Comparative Example 2 Distilled water Distilled water - 30 parts by weight - Comparative Example 3 EtOH EtOH - - - Comparative Example 4 EtOH EtOH - 30 parts by weight -

Experimental example

dehydration assessment

After drying the biogel sample prepared in Example 1 for 24 hours, a photograph of the dried biogel is shown in FIG. 1 .

1 shows a photograph after drying for 24 hours of the biogel prepared in Examples 1-1 to 1-6 of the present invention.

Referring to FIG. 1, in the biogels prepared in Examples 1-1 to 1-6, as the amount of sodium chloride added as a salt increases, the dehydration of the biogel increases in the post-treatment process, thereby shortening the drying time. It was confirmed that it could be shortened.

Moisture absorption evaluation

The water absorption of the biogel prepared in Example 1 was measured as follows.

The biogel prepared in Example 1 was completely dried, and after measuring the mass of the dried biogel, it was immersed in saline or distilled water for 24 hours. Thereafter, the biogel is taken out and the water falling for 5 minutes is removed, and then the biogel after 10 minutes, 20 minutes, 30 minutes, 1 hour, 2 hours, 3 hours and 24 hours through the following formula 1 The water absorption was calculated by measuring the mass of each.

[Equation 1]

W _t = (M _t - M ₀ )/M ₀

In Equation 1, W _t is the water absorption amount (g / g) for saline or distilled water after t minutes or t hours, M _t is the mass (g) of the biogel after immersion for t minutes or t hours, M ₀ is the mass (g) of the initially dried biogel. At this time, t is 10 minutes, 30 minutes, 1 hour, 3 hours and 24 hours.

Thereafter, the water absorption amount of the biogels prepared in Examples 2 to 5 and Comparative Examples 1 to 4 was calculated in the same manner, and the calculated water absorption amounts are shown in Tables 2 to 8, respectively.

Saline absorption (g/g) 10 minutes later 30 minutes later 1 hour later 3 hours later 24 hours later Comparative Example 1 9.6 12.7 13.2 13.8 14.4 Example 1-1 7.7 9.3 9.7 9.8 10.5 Example 1-2 7.9 9.3 9.5 9.8 10.7 Examples 1-3 8.6 9.8 10.2 11.6 11.8 Example 1-4 9.4 10.9 11.6 11.7 12.3 Example 1-5 9.3 9.6 9.6 10.5 11.4 Example 1-6 7.4 7.9 8.4 9.0 10.2

Saline absorption (g/g) 10 minutes later 30 minutes later 1 hour later 3 hours later 24 hours later Comparative Example 1 9.6 12.7 13.2 13.8 14.4 Example 2-1 10.3 12.0 12.7 13.3 14.4 Example 2-2 9.6 11.3 12.1 12.8 12.9 Example 2-3 9.3 9.7 10.5 10.6 12.6 Example 2-4 9.5 10.3 10.5 11.0 12.4 Example 2-5 10.7 12.2 12.4 13.1 13.1 Example 2-6 8.0 8.9 10.2 10.9 12.5

Saline absorption (g/g) 10 minutes later 30 minutes later 1 hour later 3 hours later 24 hours later Comparative Example 2 13.1 15.9 16.3 17.2 18.9 Example 3-1 14.0 16.0 16.3 16.9 18.8 Example 3-2 13.1 15.1 15.7 16.4 17.0 Example 3-3 13.0 13.8 14.3 15.2 16.0 Example 3-4 13.5 14.0 14.3 15.4 16.0 Example 3-5 14.9 15.9 16.0 16.7 16.9 Example 3-6 12.1 13.4 14.0 14.7 15.8

Saline absorption (g/g) 10 minutes later 30 minutes later 1 hour later 3 hours later 24 hours later Comparative Example 3 12.3 16.7 20.1 22.8 27.3 Example 4-1 9.6 12.9 14.3 14.4 25.1 Example 4-2 11.9 17.7 19.2 21.7 28.4 Example 4-3 15.9 18.2 22.0 24.8 32.1

Distilled water absorption (g/g) 10 minutes later 30 minutes later 1 hour later 3 hours later 24 hours later Comparative Example 3 16.4 30.9 37.0 49.4 50.8 Example 4-1 16.1 28.7 32.8 38.0 50.1 Example 4-2 26.8 39.1 43.6 49.0 59.1 Example 4-3 31.0 43.1 44.6 51.7 62.4

Saline absorption (g/g) 10 minutes later 30 minutes later 1 hour later 3 hours later 24 hours later Comparative Example 4 16.4 21.0 24.2 26.2 31.0 Example 5-1 15.1 16.9 18.4 18.9 29.7 Example 5-2 15.9 24.1 23.9 26.8 36.4 Example 5-3 20.4 25.1 28.7 30.9 40.4

Distilled water absorption (g/g) 10 minutes later 30 minutes later 1 hour later 3 hours later 24 hours later Comparative Example 4 32.1 42.8 46.1 52.4 62.4 Example 5-1 30.2 34.1 37.5 39.4 52.4 Example 5-2 32.1 46.7 49.7 53.8 70.1 Example 5-3 39.8 50.1 58.5 62.5 79.4

Evaluation of water retention and solids content

Water retention and solid content of the biogel prepared in Example 2 were measured as follows.

Specifically, a cellulose gel sample immersed and repeatedly washed in Example 2 was prepared, the sample was filtered through a 200 mesh mesh, and the weight of the wet sample filtered on the 200 mesh mesh was measured. Thereafter, the wet sample was completely dried in a dryer at 105° C., and the weight of each dry sample was measured. Then, water retention was calculated according to Equation 2 below, and solid content was calculated according to Equation 3 below.

[Equation 2]

R = (W-D)/D

[Equation 3]

L = D/W X 100

In Equation 2, R is the water retention amount (g/g) of the cellulose gel, W is the weight (g) of the wet sample, and D is the dry weight (g) of the sample. In Equation 2, L is the solid content (%), W is the weight (g) of the wet sample, and D is the dry weight (g) of the sample.

Thereafter, the water retention and solid content of the biogel prepared in Comparative Example 1 were calculated in the same manner, and the calculated water retention and solid content are shown in Table 9 below.

Water retention (g/g) Solid content (%) Comparative Example 1 2000 0.5 Example 2-1 230 4.3 Example 2-2 130 7.7 Example 2-3 90 11.1 Example 2-4 60 19 Example 2-5 45 29 Example 2-6 20 50.0

Referring to Tables 2 to 4 and Table 9, prepared in Examples 1-1 to 1-6, Examples 2-1 to 2-6, and Examples 3-1 to 3-6 It was confirmed that the solids content of the prepared biogel increased as the amount of sodium chloride added as a salt increased, and the water absorption and water retention of the biogel decreased. Through this, it can be seen that the biogel according to the present invention can shorten the drying time by increasing the dehydration of the biogel in the post-treatment process.

Referring to Tables 5 to 8, in the case of Comparative Examples 3 and 4, as an existing process of solvent-exchanging and drying water inside the gel using an organic solvent when manufacturing a cellulose-based biogel, in the washing and drying process, the gel It was confirmed that although the process efficiency was inferior to Example 4 and Example 5 because more than 50 times the organic solvent compared to the dry weight of was used, the water absorption amount was similar. Through this, the biogels according to Examples 4 and 5 are washed with water or saline to dehydrate the water inside the gel, and then use only 1 to 3 times ethanol compared to the dry weight in the washing and drying process, so economic and safety This is excellent, and it can be seen that the physical properties of the prepared biogel are also excellent. In addition, in the case of including the absorbent structure including the biogel, it can be confirmed that it can be effectively used for applications requiring absorption of water containing salts in addition to distilled water. Accordingly, the biogel according to the present invention is soil It can be seen that it can be applied to various types of absorbent articles such as hygiene products and hydro patches in addition to moisture control agents, absorbent pads, and ice packs.

Therefore, the biogel manufacturing method according to the present invention uses saline during the reaction or in the post-treatment process, thereby rapidly dehydrating the gel without using a separate organic solvent in the post-treatment process and shortening the drying time, thereby improving economics and safety. On the other hand, the prepared biogel does not flow into an aqueous solution when it absorbs moisture, but solidifies or gelates to form a water-holding structure, and has excellent water absorption and water retention compared to its own weight, and an absorbent article including the same. It can be seen that can be produced.

The foregoing detailed description is intended to illustrate and explain the present invention. In addition, the foregoing merely represents and describes preferred embodiments of the present invention, and as described above, the present invention can be used in various other combinations, modifications, and environments, and the scope of the inventive concept disclosed herein, the foregoing Changes or modifications are possible within the scope equivalent to the disclosure and / or within the scope of skill or knowledge in the art. Accordingly, the above detailed description of the invention is not intended to limit the invention to the disclosed embodiments. Also, the appended claims should be construed to cover other embodiments as well.

Claims (15)

Preparing a cellulose suspension containing a cellulose raw material including at least one of a cellulose derivative and cellulose fibers;
preparing a cellulose gel by adding an acrylic monomer, a polymerization initiator and a crosslinking agent to the cellulose suspension;
immersing the cellulose gel in water or saline;
washing the immersed cellulose gel; and
A method for producing a bio-gel comprising: preparing a cellulose gel mixture by mixing and homogenizing a salt in the washed cellulose gel. According to claim 1,
The content of the cellulose raw material is 1 part by weight or more and 10 parts by weight or less based on 100 parts by weight of the cellulose suspension. According to claim 1,
Wherein the acrylic monomer comprises at least one of an acrylic acid monomer, an acrylic ester monomer, and an acrylamide monomer. According to claim 1,
The amount of the acrylic monomer is 5 parts by weight or more and 15 parts by weight or less based on 100 parts by weight of the cellulose suspension. According to claim 1,
The step of preparing the cellulose gel; is a method for producing a bio-gel that is performed for 30 minutes to 3 hours at a temperature of 50 ℃ or more and 80 ℃ or less. According to claim 1,
immersing the cellulose gel in water or saline; is carried out for a time of 1 hour or more and 24 hours or less,
A method for producing a bio-gel comprising mixing the water or saline and the cellulose gel at a weight ratio of 5:1 or more and 20:1 or less. According to claim 1,
The brine is a method for producing a bio-gel containing the salt. According to claim 1,
The salt is a method for producing a bio-gel comprising at least one of sodium chloride, potassium chloride, calcium chloride and magnesium chloride. According to claim 1,
Based on 100 parts by weight of the total weight of the washed cellulose gel and the salt, the salt content is 0.5 parts by weight or more and 30 parts by weight or less. According to claim 1,
Preparing the cellulose gel mixture;
Further comprising: mixing the homogenized cellulose gel and polar group-containing cellulose,
The bio-gel manufacturing method of mixing the polar group-containing cellulose in an amount of 5 parts by weight or more and 30 parts by weight or less with respect to 100 parts by weight of the homogenized cellulose gel. According to claim 10,
Wherein the polar group-containing cellulose includes at least one of a carboxyl group-containing cellulose, an acetyl group-containing cellulose, a nitro group-containing cellulose, and a hydroxyl group-containing cellulose. According to claim 1,
Further comprising preparing a biogel by dehydrating, drying, and pulverizing the cellulose gel mixture,
Wherein the grinding is to adjust the particle size of the dried cellulose gel mixture to a diameter of 0.1 mm or more and 1 mm or less. According to claim 12,
Preparing the bio-gel;
Further comprising the step of further washing the dehydrated cellulose gel mixture with an organic solvent,
The organic solvent is mixed with the dehydrated cellulose gel mixture in a weight ratio of 1: 1 or more and 5: 1 or less. A bio-gel prepared by the method according to claim 1. An absorbent structure comprising the biogel according to claim 14,
The absorbent article of claim 1, wherein the water absorption rate of the absorbent structure is 10 times or more and 30 times or less compared to its own weight.

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